linux-stable/block
Tejun Heo f1de2439ec blk-iocost: revamp donation amount determination
iocost has various safety nets to combat inuse adjustment calculation
inaccuracies. With Andy's method implemented in transfer_surpluses(), inuse
adjustment calculations are now accurate and we can make donation amount
determinations accurate too.

* Stop keeping track of past usage history and using the maximum. Act on the
  immediate usage information.

* Remove donation constraints defined by SURPLUS_* constants. Donate
  whatever isn't used.

* Determine the donation amount so that the iocg will end up with
  MARGIN_TARGET_PCT budget at the end of the coming period assuming the same
  usage as the previous period. TARGET is set at 50% of period, which is the
  previous maximum. This provides smooth convergence for most repetitive IO
  patterns.

* Apply donation logic early at 20% budget. There's no risk in doing so as
  the calculation is based on the delta between the current budget and the
  target budget at the end of the coming period.

* Remove preemptive iocg activation for zero cost IOs. As donation can reach
  near zero now, the mere activation doesn't provide any protection anymore.
  In the unlikely case that this becomes a problem, the right solution is
  assigning appropriate costs for such IOs.

This significantly improves the donation determination logic while also
simplifying it. Now all donations are immediate, exact and smooth.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andy Newell <newella@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-01 19:38:32 -06:00
..
partitions block: remove the disk argument to delete_partition 2020-09-01 19:38:25 -06:00
Kconfig blk-wbt: Remove obsolete multiqueue I/O scheduling comment 2020-09-01 16:49:26 -06:00
Kconfig.iosched treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile blk-mq: merge blk-softirq.c into blk-mq.c 2020-06-24 09:15:56 -06:00
badblocks.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
bfq-cgroup.c bfq: fix blkio cgroup leakage v4 2020-08-18 07:48:08 -07:00
bfq-iosched.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
bfq-iosched.h bfq: fix blkio cgroup leakage v4 2020-08-18 07:48:08 -07:00
bfq-wf2q.c bfq: fix blkio cgroup leakage v4 2020-08-18 07:48:08 -07:00
bio-integrity.c block: make function __bio_integrity_free() static 2020-07-02 12:38:18 -06:00
bio.c block: Fix page_is_mergeable() for compound pages 2020-08-17 19:35:53 -07:00
blk-cgroup-rwstat.c blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT 2019-11-07 12:28:13 -07:00
blk-cgroup-rwstat.h blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT 2019-11-07 12:28:13 -07:00
blk-cgroup.c blkcg: fix memleak for iolatency 2020-08-21 17:14:27 -06:00
blk-core.c blk-mq: use BLK_MQ_NO_TAG for no tag 2020-09-01 16:49:26 -06:00
blk-crypto-fallback.c block: rename generic_make_request to submit_bio_noacct 2020-07-01 07:27:24 -06:00
blk-crypto-internal.h block: blk-crypto-fallback for Inline Encryption 2020-05-14 09:48:03 -06:00
blk-crypto.c block: rename generic_make_request to submit_bio_noacct 2020-07-01 07:27:24 -06:00
blk-exec.c block: add a blk_account_io_merge_bio helper 2020-05-27 05:21:23 -06:00
blk-flush.c block: fix double account of flush request's driver tag 2020-08-11 13:53:32 -06:00
blk-integrity.c block: Make blk-integrity preclude hardware inline encryption 2020-05-14 09:48:03 -06:00
blk-ioc.c block: remove retry loop in ioc_release_fn() 2020-07-16 10:22:15 -06:00
blk-iocost.c blk-iocost: revamp donation amount determination 2020-09-01 19:38:32 -06:00
blk-iolatency.c blk-iolatency: only call ktime_get() if needed 2020-07-01 08:02:38 -06:00
blk-lib.c block: check queue's limits.discard_granularity in __blkdev_issue_discard() 2020-08-05 17:15:47 -06:00
blk-map.c block: remove the BIO_USER_MAPPED flag 2020-09-01 16:49:26 -06:00
blk-merge.c block: Add a new helper to attempt to merge a bio 2020-09-01 16:49:26 -06:00
blk-mq-cpumap.c blk-mq: balance mapping between present CPUs and queues 2019-08-04 21:43:12 -06:00
blk-mq-debugfs-zoned.c
blk-mq-debugfs.c for-5.9/block-20200802 2020-08-03 11:57:03 -07:00
blk-mq-debugfs.h blk-mq: no need to check return value of debugfs_create functions 2019-06-13 03:00:30 -06:00
blk-mq-pci.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-rdma.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-sched.c blk-mq: use BLK_MQ_NO_TAG for no tag 2020-09-01 16:49:26 -06:00
blk-mq-sched.h block: blk-mq: Remove blk_mq_sched_started_request and started_request 2019-07-23 07:25:09 -06:00
blk-mq-sysfs.c blk-mq: make sure that line break can be printed 2019-11-04 07:14:10 -07:00
blk-mq-tag.c blk-mq: move blk_mq_get_driver_tag into blk-mq.c 2020-06-30 12:57:59 -06:00
blk-mq-tag.h blk-mq: centralise related handling into blk_mq_get_driver_tag 2020-07-08 16:06:42 -06:00
blk-mq-virtio.c blk-mq: Fix typo in comment 2020-03-17 20:55:21 +01:00
blk-mq.c blk-mq: insert request not through ->queue_rq into sw/scheduler queue 2020-08-21 17:09:22 -06:00
blk-mq.h Revert "blk-mq: put driver tag when this request is completed" 2020-07-01 22:58:32 -06:00
blk-pm.c scsi: block: pm: Simplify resume handling 2020-07-24 22:09:55 -04:00
blk-pm.h
blk-rq-qos.c Revert "blk-rq-qos: remove redundant finish_wait to rq_qos_wait." 2020-07-15 09:33:37 -06:00
blk-rq-qos.h blk-rq-qos: fix first node deletion of rq_qos_del() 2019-10-15 10:13:13 -06:00
blk-settings.c block: remove blk_queue_stack_limits 2020-07-20 15:38:52 -06:00
blk-stat.c blk-stat: make q->stats->lock irqsafe 2020-09-01 16:48:46 -06:00
blk-stat.h
blk-sysfs.c block: add max_active_zones to blk-sysfs 2020-07-15 14:26:11 -06:00
blk-throttle.c block: rename generic_make_request to submit_bio_noacct 2020-07-01 07:27:24 -06:00
blk-timeout.c block: blk-timeout: delete duplicated word 2020-07-31 16:29:47 -06:00
blk-wbt.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
blk-wbt.h blk-wbt: remove wbt_update_limits 2020-05-29 16:30:39 -06:00
blk-zoned.c block: don't do revalidate zones on invalid devices 2020-08-03 09:24:04 -06:00
blk.h block: remove the disk argument to delete_partition 2020-09-01 19:38:25 -06:00
bounce.c block: rename generic_make_request to submit_bio_noacct 2020-07-01 07:27:24 -06:00
bsg-lib.c bsg-lib: convert comma to semicolon 2020-08-16 20:07:12 -07:00
bsg.c compat_ioctl: bsg: add handler 2020-01-03 09:33:21 +01:00
cmdline-parser.c
elevator.c block: elevator: delete duplicated word and fix typos 2020-07-31 16:29:47 -06:00
genhd.c block: remove the unused q argument to part_in_flight and part_in_flight_rw 2020-09-01 19:38:31 -06:00
ioctl.c block: Fix type of first compat_put_{,u}long() argument 2020-05-19 09:40:29 -06:00
ioprio.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
keyslot-manager.c block/keyslot-manager: use kvfree_sensitive() 2020-06-29 13:24:05 -06:00
kyber-iosched.c block: Move blk_mq_bio_list_merge() into blk-merge.c 2020-09-01 16:49:26 -06:00
mq-deadline.c blk-mq: remove the bio argument to ->prepare_request 2020-05-29 10:23:24 -06:00
opal_proto.h block: sed-opal: Change the check condition for regular session validity 2020-03-12 08:00:10 -06:00
scsi_ioctl.c scsi: core: Allow non-root users to perform ZBC commands 2020-03-16 18:26:31 -04:00
sed-opal.c block: sed-opal: Change the check condition for regular session validity 2020-03-12 08:00:10 -06:00
t10-pi.c block: Allow t10-pi to be modular 2020-01-06 20:59:04 -07:00